1. Field of the Invention
This invention relates to a method for managing the operation of an apparatus for the reaction of gas phase partial oxidation of an unsaturated hydrocarbon with a molecular oxygen-containing gas and to a method for the production of (meth)acrylic acid. More particularly, it relates to a method for managing the operation of an apparatus for the reaction of gas phase oxidation such as for the production of acrylic acid or acrolein by the gas phase partial oxidation of propylene with a molecular oxygen-containing gas, the production of methacrylic acid or methacrolein by the gas phase partial oxidation of isobutylene, and the production of ethylene oxide by the gas phase partial oxidation of ethylene and a method for the production of (meth)acrylic acid.
2. Description of the Related Art
Since such oxidizable raw materials as propylene, isobutylene, and ethylene are generally formed an explosive mixture by being mixed with molecular oxygen, the flow rate of such a raw material and the flow rate of a molecular oxygen-containing gas are so set that the composition of the raw material gas may normally avoid entering the inflammable area.
The management of the composition of a raw material gas, therefore, is executed by controlling the flow rate of each of the gases at a set value. Since this method of management possibly suffers the composition of the gas to fall within the inflammable area when such a measuring instrument as a flow meter encounters abnormality, it requires the composition of the gas to be detected by a proper method.
As a way of detecting the composition of a raw material gas, the analysis by means of various online analyzing instruments generally prevails. In the case of the conventional device for the reaction of gas phase oxidation, when the value of the composition of a raw material gas measured by the analysis deviates from the preset range, this device is at once brought to emergency stop automatically as by a process control device, for example. Conceivably, the preset values of various flow rates may be automatically controlled by the indications on analyzing instruments (refer to the official gazette of JP-A-2001-122805, the official gazette of JP-A-2001-114706, and the official gazette of JP-A-2001-120984, for example).
In the case of such a device, however, even when the value of the composition of a raw material gas actually measured happens to represent a deviation from the range of preset value, it is not necessarily improbable that this deviation originates in an erroneous operation of the device. The stop of the operation of the device in response to this deviation inevitably jeopardizes the economy of the operation itself.
It is, therefore, an object of this invention to provide a novel method for managing the operation of an apparatus for the reaction of gas phase oxidation.
Another object of this invention is to provide a novel method for managing the operation of an apparatus for the reaction of gas phase oxidation which excels in safety and economy.